The present invention relates to a water aerator used in a hand washing apparatus, water faucet, etc.
A water aerator provided with an inlet for wash water, an outlet for a bubbly stream, and an air mixing mechanism disposed in a wash water passage extending between the inlet for wash water and the outlet for the bubbly stream is disclosed in U.S. Pat. No. 5,114,072. In the water aerator, the air mixing mechanism has a pressure reducing disk provided with a plurality of pores and blocking the wash water passage, air inlets formed in the circumferential wall of the wash water passage downstream of the pressure reducing disk, and a rectifying mesh disposed downstream of the air inlets.
In the water aerator of U.S. Pat. No. 5,114,072, a shower of wash water discharges from the plurality of pores in the pressure reducing disk. The shower of wash water entrains air flowing into the wash water passage through the air inlets due to friction working between them and collides against the rectifying mesh. The air entrained by the shower of wash water becomes an abundance of air bubbles when the shower of wash water passes through the rectifying mesh to be broken up. The air bubbles disperse in the wash water to form a bubbly stream of wash water. The bubbly stream of wash water discharges from the outlet for the bubbly stream.
The shower of wash water must be prevented from discharging from the pores of the pressure reducing disk at a high speed so as to prevent a backflow of the wash water toward the air inlets. This is because the wash water cannot pass through the rectifying mesh at a high speed due to the large flow resistance of the rectifying mesh. Therefore, the water aerator of U.S. Pat. No. 5,114,072 has a disadvantage in that it cannot discharge the shower of wash water at a high speed from the pores of the pressure reducing disk, suck a large quantity of air entrained by the high-speed shower of wash water, propel the high-speed shower of wash water against the rectifying mesh to break it up, and mix a large quantity of air with the shower of wash water.
Therefore, an object of the present invention is to provided a water aerator which can discharge a shower of wash water at a high speed from pores in a pressure reducing disk, suck a large quantity of air, and mix a large quantity of air with the wash water.
In one aspect, the present invention provides a water aerator comprising an inlet for wash water, an outlet for a bubbly stream, first means for mixing air with wash water disposed in a wash water passage extending between the inlet for wash water and the outlet for the bubbly stream, and second means for rectifying the wash water disposed downstream of the first means, wherein the first means comprises a pressure reducing disk provided with a plurality of pores and blocking the wash water passage, air inlets formed in a circumferential wall of the wash water passage downstream of the pressure reducing disk, and a tapered zone of the wash water passage with conically diminishing diameter disposed downstream of the pressure reducing disk, wherein the second means comprises a rectifying zone of the wash water passage extending between the downstream end of the tapered zone and the outlet for the bubbly stream, and a honeycomb disposed in the rectifying zone, and wherein the pores in the pressure reducing disk are directed to a circumferential wall of the tapered zone.
In the water aerator of the present invention, a shower of wash water discharges from the plurality of pores in the pressure reducing disk. The shower of wash water entrains air flowing into the wash water passage through the air inlets due to friction working between them and collides against the tapered zone of the wash water passage to be broken up. When the shower of wash water is broken up, the air entrained by the shower of wash water becomes an abundance of air bubbles to disperse in the wash water, thereby forming a bubbly stream of the wash water. The bubbly stream of the wash water passes through the tapered zone into the rectifying zone to be rectified by passing through the rectifying zone and also by passing through the honeycomb. The rectified bubbly stream discharges from the outlet for the bubbly stream.
In the water aerator according to the present invention, the bubbly stream can pass through the honeycomb at a high speed because the flow resistance of the honeycomb is less than that of the rectifying mesh. Therefore, the water aerator in accordance with the present invention can discharge the shower of wash water at a high speed from the pores in the pressure reducing disk, suck a large quantity of air, and mix a large quantity of air with the wash water.
In accordance with a preferred embodiment of the present invention, a circumferential wall of the rectifying zone continuously connects with the circumferential wall of the tapered zone.
In this embodiment of the water aerator, a part of the bubbly stream running along the circumferential wall of the tapered zone flies off the downstream end of the tapered zone toward the radial center of the rectifying zone to gather and form a converged stream there. The remaining part of the bubbly stream running along the circumferential wall of the tapered zone passes by the downstream end of the tapered zone into the rectifying zone to run along the circumferential wall of the rectifying zone without flying out the downstream end of the tapered zone, thereby forming a cylindrical film of water. The converged bubbly stream passes through the central portion of the honeycomb. The cylindrical film of the bubbly stream is divided into an abundance of fine converged flows dispersed in the circumferential direction and in the radial direction when it passes through the honeycomb. The converged bubbly stream discharges from the central portion of the outlet for the bubbly stream and an abundance of fine converged bubbly streams uniformly dispersed in the circumferential direction and in the radial direction discharge from all portions of the outlet for the bubbly stream other than the central portion. The central converged bubbly stream and an abundance of the fine converged bubbly streams uniformly dispersed around the central converged bubbly stream are united to form a stable, thick converged bubbly stream. The stable, thick converged bubbly stream is visually satisfying to the user of a hand washing apparatus equipped with the water aerator.
In accordance with a preferred embodiment of the present invention, the pores in the pressure reducing disk are disposed at a constant pitch along a circle with a diameter larger than that of the downstream end of the tapered zone of the wash water passage.
In this embodiment of the water aerator, it is possible to direct the pores at right angles to end faces of the pressure reducing disk, and discharge the wash water from the pores without deflecting stream lines of the wash water directed at right angles to the end faces of the pressure reducing disk because the pores in the pressure reducing disk are disposed along a circle with a diameter larger than that of the downstream end of the tapered zone of the wash water passage. Pressure loss due to deflections of the stream lines of the wash water is not generated. Therefore, the shower of wash water discharges at a high speed from the pores in the pressure reducing disk.
In accordance with a preferred embodiment of the present invention, inlet side corners of the pores in the pressure reducing disk are rounded.
In this embodiment of the water aerator, it is possible to prevent contraction of the flows of the wash water passing through the pores and reduction of flow speed of the shower of wash water because inlet side corners of the pores in the pressure reducing disk are rounded.
In accordance with a preferred embodiment of the present invention, the air inlets are disposed upstream of the tapered zone.
In this embodiment of the water aerator, the quantity of sucked air increases and the quantity of air mixed with the wash water increases because the air inlets are disposed close to the high-speed shower of wash water before the collision against the tapered zone of the wash water passage.
In accordance with a preferred embodiment of the present invention, the corner at the connection of the circumferential wall of the tapered zone with the circumferential wall of the rectifying zone is rounded.
In this embodiment of the water aerator, flow resistance at the connection of the tapered zone with the rectifying zone is reduced and the speed reduction of the bubbly stream at the connection of the tapered zone with the rectifying zone is prevented because the corner at the connection of the circumferential wall of the tapered zone with the circumferential wall of the rectifying zone is rounded.
In accordance with a preferred embodiment of the present invention, the rectifying zone of the wash water passage increases in diameter toward the downstream.
In this embodiment of the water aerator, the outlet for bubbly stream increases in diameter, the bubbly stream discharging from the outlet for bubbly stream increases in diameter, and the user of a hand washing apparatus is more visually satisfied because the rectifying zone of the wash water passage increases in diameter toward the downstream.
In accordance with a preferred embodiment of the present invention, the honeycomb comprises a central hole and a plurality of peripheral holes disposed radially around the central hole.
In this embodiment of the water aerator, the converged bubbly stream running through the central portion of the rectifying zone passes through the central hole without interfering with partitions of the honeycomb and without becoming turbulent. The cylindrical curtain of the bubbly stream running along the circumferential wall of the rectifying zone passes through the plurality of peripheral holes disposed radially around the central hole to form an abundance of fine converged bubbly streams uniformly dispersed in the circumferential direction and in the radial direction around the converged bubbly stream passed through the central hole. The central converged bubbly stream without turbulence and an abundance of the peripheral fine converged bubbly streams uniformly dispersed in the circumferential direction and in the radial direction around the central converged bubbly stream are united to form a stable, thick converged bubbly stream. The user of a hand washing apparatus is visually satisfied by the stable, thick converged bubbly stream.
In accordance with a preferred embodiment of the present invention, the holes of the honeycomb increase in diameter toward the downstream.
In this embodiment of the water aerator, the converged bubbly streams discharging from the holes of the honeycomb come close to each other and unite easily because the holes of the honeycomb increase in diameter toward the downstream.
In accordance with a preferred embodiment of the present invention, the rectifying zone extends downstream beyond the honeycomb.
In this embodiment of the water aerator, the central converged bubbly stream and an abundance of the fine converged bubbly streams unite easily because the rectifying zone extends downstream beyond the honeycomb.
In accordance with a preferred embodiment of the present invention, the water aerator further comprises means for preventing backflow of the wash water toward the air inlets.
In this embodiment of the water aerator, clogging of the air inlets by the wash water is prevented and stoppage of air suction is prevented by the means for preventing backflow.
In accordance with a preferred embodiment of the present invention, the water aerator comprises an internal cylinder provided with the air inlets, the tapered zone, the rectifying zone and the honeycomb and receiving the pressure reducing disk, and an external cylinder receiving the internal cylinder and forming an air passage communicating with the air inlets between itself and the internal cylinder.
The provision of the internal cylinder and the external cylinder reduces the number of elements of the water aerator and facilitates the work of assembling the water aerator.
In accordance with a preferred embodiment of the present invention, the water aerator comprises an internal cylinder provided with the air inlets, the tapered zone, the rectifying zone and the honeycomb and receiving the pressure reducing disk united with the means for preventing backflow, and an external cylinder receiving the internal cylinder and forming an air passage communicating with the air inlets between itself and the internal cylinder.
The provision of the internal cylinder and the external cylinder reduces the number of elements of the water aerator, facilitates the work of assembling the water aerator, and prevents backflow of the wash water toward the air inlets.
In accordance with a preferred embodiment of the present invention, the water aerator comprises a flow regulating valve disposed upstream of the pressure reducing disk.
The provision of the flow regulating valve suppresses fluctuation of the flow rate of the discharging wash water due to fluctuation of the supply pressure of the wash water and stabilizes the discharging of the wash water.
In accordance with a preferred embodiment of the present invention, the water aerator discharges the bubbly stream at a flow rate of wash water of 2 L/minute and 100 volume % of air mixed with the wash water.
The user of a hand washing apparatus equipped with the water aerator is tactually satisfied by the flow rate of the wash water onto the palms and visually satisfied by the bubbly stream with a 4 L/minute flow rate.
In another aspect, the present invention provides a hand washing apparatus equipped with any one of the aforementioned water aerators.
In another aspect, the present invention provides a water faucet provided with any one of the aforementioned water aerators.
The water aerator in accordance with the present invention can be used for a hand washing apparatus, a water faucet, etc.